Evaluation of diffusion length at different excess carrier concentrations

✍ Scribed by D. Cavalcoli; A. Cavallini

• Book ID: 103954866
• Publisher: Elsevier Science
• Year: 1994
• Tongue: English
• Weight: 251 KB
• Volume: 24
• Category: Article
• ISSN: 0921-5107
• DOI: 10.1016/0921-5107(94)90306-9

✦ Synopsis

The charge collection technique of scanning electron microscopy is widely used to measure the minority carrier diffusion length L in semiconductors. In order to obtain L, the continuity equation for the excess carder concentration Ap must be solved with suitable boundary conditions. L is supposed to be constant as a function of the excess carrier concentration. This paper investigates the diffusion length in Si and GaAs in low and high injection regimes, where L is independent of the injection conditions. The results obtained are discussed on the basis of the Shockley-Read-Hall recombination model (W. Shockley and W. Read, Phys. Rev., 87 (1952) 835). The evaluation of the injection dose is also discussed. Indeed, this is very different for the semiconductors under investigation, due to their different electronic properties.